The U.S. Army has commissioned Chicago-based toy company Lund and Company Invention to build a gun that can shoot bullets at varying speeds. The idea for the gun was inspired by Lund’s hydrogen-powered toy rocket.

According to CEO Bruce Lund, the combustion chamber behind the bullet will contain a mix of air and either a liquid or gaseous fuel. This mixture will control the explosive capability of the propellant, which determines the velocity of the bullet.

Currently, soldiers and police officers use different guns for lethal and nonlethal use. The VWS would allow them to use the same gun for all purposes, but some experts believe this is risky.

Lund is building a .50 caliber rifle, but he says that future VWS designs will be available in sizes from “handgun to Howitzer.” He plans to have a prototype built within six months and hopes to have it in production within 18 months.

Lund’s hydrogen-powered rocket uses electrolysis of water, which separates the oxygen and hydrogen components of water. When the separated molecules are heated, the hydrogen fuel ignites and shoots the rocket into the air. A diagram and explanation of the rocket is provided in Lund’s patent.

The obvious benefit of the VWS is the ability for authorities to quickly switch between lethal and nonlethal force. The blog “All info off guns” suggests other advantages of the VWS: “Long range shooters would appreciate a higher velocity, as this would prevent muzzle drop. Also, anyone using a silencer would appreciate reducing the muzzle velocity to subsonic levels in order to further quiet the weapon.”